Due to rule 1, one can imagine that on an extremal surface associated with an entropy \(S\)  (i.e., with an area of \(4{G_N}S\) ), there distribute exactly \(S\)  bits (each with only two basic states, \(\left| 1 \right\rangle \)  and \(\left| 0 \right\rangle \) ). Then, for any bulk extremal surface \(\gamma \)  with an entropy \({S_\gamma }\) , we can label its basic states as \(\left\lbrace  {\left| {\gamma = q} \right\rangle \left| {q \in N,0 \le q \le {2^{{S_\gamma }}} - 1} \right.} \right\rbrace \) . Each decimal number \(q\)  exactly corresponds to a binary string that describes the overall configuration state of all the SS bits on \(\gamma \) . The SS state corresponding to \(\gamma \)  can be represented as a mixed state \({\rho _\gamma }\)  equipped with equal probabilities [1]}:
\({\rho _\gamma } = \sum \limits _{q = 0}^{{2^{{S_\gamma }}} - 1} {\frac{1}{{{2^{{S_\gamma }}}}}\left| {\gamma = q} \right\rangle \left\langle {\gamma = q} \right|} .\) 
